Method of treating cellulosic textile materials



Patented Jan. 1, 1946 METHOD OF TREATING CELLULOSIC TEX- TILE MATERIALS William J. Burke,

Wilmington, Del., assignor to E. I. du Pont de Nemours & Company, Wilmington, Del., a corporation of Delaware No Drawing. Application January I, 1942, Serial No. 425,940

(or. s-iiasl 12 Claims.

This invention relates to the chemical modification of cellulosic textile materials. More particularly it relates to the chemical modification of celluloslc textile materials whereby to render the same receptive to acid and chrome dyes used with wool, and to improve the crush resistance of such materials.

Celluloslc fibers are being used in increasing amounts in admixture with wool to create novel textiles not obtainable with either fiber alone, and to lower the raw materials cost of woolcontaining products. This situation has made it desirable to obtain modified cellulosic fibers which can be dyed with wool dyes in order to avoid the complications and expense arising from the use of a mixture of dyes or a two-bath dyeing process. Further, in certain instances it is desirable to improve simultaneously the crush resistance of cellulosic textile materials, which are notably inferior to wool in this respect.

A variety of treatments have been described for modifying celluloslc textiles in order to give them affinity for the acid and chrome dyes used with wool. For example, it has been proposed to react regenerated cellulose filaments and fibers with an aminoaldehyde, say dimethylaminoacetaldehyde, whereby the aldehyde group is attached to the cellulose by the formation of an acetal group. In still other processes heretofore described, the cellulosic textile material is first modified by treatment with an aldehyde, and is subsequently reacted with one or more of a large variety of nitrogenous compounds, prominent among which are the amines. In general, however, these methods have not been entirely satisfactory since the dyeings obtained are often deficient in fastness to light and washing and/or are dull and lack uniformity. In addition, high cost, complicated procedure, and lack of afllnity for a wide range of dyestuffs make many of the previously described treatments unsatisfactory from a commercial standpoint.

Many of the treatments which have been proposed for improving the crush resistance of cellulosic textiles reduce the affinity of these materials for direct dyes to an objectionable degree. This is particularly true in treatments involving formaldehyde.

An object of this invention, therefore, is to modif cellulosic textile materials so that they will have good affinity for acid and chrome dyes and improved crush resistance, by a simple procedure utilizing inexpensive and readil available raw materials. Another object is to prepare new cellulosic textile materials which can be dyed to a full shade with a wide range of wool as well as direct cotton dyes to yield colored products having good fastness to light and soaplng. A still further object resides in the treatment of regenerated cellulose textile materials with inexpensive reagents which render the materials receptive to a wide range of direct, acid, and chrome dyes and which. in addition, enhance the crush resistance of such materials. Further objects will appear hereinafter.

These objects are accomplished by this invention, the essentials of which, briefly stated, are as follows: Cellulosic textile materials are intimately contacted with an aqueous solution comprising formaldehyde or a formaldehydeyielding material, a salt of a water-soluble tertiary hydroxyalkylarnine, each hydroxyl group of which is at least 2 carbon atoms removed from the amino nitrogen, and an acidic catalyst; thereafter the materials are dried and the reaction is completed by heat-treating the dried materials at an elevated temperature. The resulting tertiary amino nitrogen-containing cellulosic textile materials. which are new and form a part of this invention, have excellent aflinit for acid, chrome and direct dyes, and improved crush resistance.

In carrying out the process of this invention a preferred procedure is as follows: The cellulosic textile material is impregnated with an aqueous formaldehyde solution containing a salt of a water-soluble tertiary hydroxyalkylamine and an acidic catalyst. The excess solution is re- 'moved by suitable means from the cellulosic material which is then dried at a temperature below C. and heated for one to ten minutes at a temperature in the range of C. to C. The treated material is rinsed with water, washed in a soap solution containing soda ash and again rinsed with water. The resulting products have excellent afiinity for a wide range of acid and chrome as well as direct dyes.

The treating solution preferably contains, by weight, from 3 to 15% formaldehyde and 3 to 30% of the tertiary hydroxyallqrlamine salt. The acid catalyst, preferably ammonium chlo ride, is used insuch an amount, generally from 0.05 to 2% depending upon the particular catalyst, that the resulting impregnating solution has a H in the range of 1.6 to 3.0. The production of crush resistant products is favored by the use of high baking temperatures, high concentrations of formaldehyde, and active catalysts which give a low pH value.

Salts suitable for use in this invention may be made by the addition of a strong mineral or organic acid to an equivalent quantity of a watersoluble tertiary hydroxyalkylamine. The preferred tertiary hydroxyalkylamines are the tertiary beta-hydroxyethylamines which are conveniently obtained by the interaction of ethylene oxide with an ammonia type compound having at least one hydrogen attached to the amino nitrogen, or by reacting a beta-hydroxyethylamlne having at least one amino hydrogen with formaldehyde and thereafter withformic acid as described in U. 8. Patent 2,168,099.

The drying step is preferably carried out at room temperature in a stream of air. It more rapid drying is desired, the material is heated at temperatures rang ng up to 70' C.

Heating or baking the impregnated and dried yarn in rapidly circulating hot air improves the uniformity of the treatment and increases the reaction rate. Preferably the baking temperature is within the range 0100' C. to 140' C. Ii desired, inert liquids such as xylene can be med as the heating medium.

The unreacted tertiary hydrolyalkylamine salt is readily recovered trom the treated yarn by concentrating the aqueous solution obtained when the yarn is rinsed after the baking step.

The invention is further illustrated by the following examples. Parts are given by weight.

Exams: I

There is described in U. 8. Patent No. 2,240,745 a crimped viscose rayon yarn which will be referred to hereinafter as Fiber D." Bkeins of 2500 denier, 100 filament "Fiber D" yarn are impregnated with an aqueous solution containing 5% formaldehyde, tris(beta-hydroxyethyllamine hydrochloride and 0.2% ammonium chloride. The treating solution has a PH of 1.0 and is used at room temperature. The impregnated yarn is centrifuged so that the amount of treating solution reta'inedis about equal to the weight of the dry yarn. After being dried at room temperature. the yarn is heated for five minutes in a chamber in which hot air at 105 C. is rapidly circulated. The treated skeins are rinsed with water. heated at 70 C. for three minutes in a 0.1% soap solution, rinsed thoroughly with water and dried. Fiber D" treated in this manner gains 5% in weight and contains 0.33% nitrogen. The treated yarn is believed to be characterized by the presence or the structural unit Cell-OCHrOCI-IzCHzN CHaCI-IsOH) 2' HC! wherein Cell represents a cellulose residue. The modified yarn has excellent amnity for a wide range of dyestufis commonly used in dyeing wool. The concentration of representative acid, chrome and direct dyes required to produce equivalent shades on wool and the modified "Fiber D" are given in the following table.

Table I Percentage used with- Rowe Color Index No. Modm "Fiber Wool ACID DYES "Pen 1" Light Yellow ox 030 i. 0 2 0 Do r o t orange G 27 l. 0 2. ii "Pontscyi" W001 Blue GL 833 l. 0 3. 0 "Poutecyl" Fast Black BBO... 807 2.0 8.0 "Pontacyl" Biiio Black sx 246 2. 0 l0. 0

CHROME DYES tachrem Fast Red E Cone... 652 1. 0 2 0 "EEtachromri" Black TA 203 6. 0 12. 0

DIRECT DYE! "P tarnine" Blue RWO 00110.... 612 1.0 20 "233mm" Green sx l. 0 2.0

1B hyde treated yarn.

amnity for the following dyes.

Table II Rowe Color Dye Index number ACID DYES Du Pont Brilliant Milling Green D Cenc so? Du Pont Anthraquinone Green G 1, 07B

CHROME DYES "Poutschrome" Flsvine A 21D "Pontachrome" Azure Blue BR 720 DIRECT DYES "Pontsmine" Fest Red SBL 278 "Pontanrine" Sky Blue 6B 518 "Pontamine Black E 681 "Pontamine" Fast Black FF 539 In all cases the dyeings on the modified D" are equal or superior in depth to the dyeings obtained with wool by the same procedure.

EXAMPLE II Skeins of bright. unfinished, 150 denier, 40 filament viscose rayon yarn are impregnated with an aqueous solution containing 5% formaldehyde, 15 methyl-bis beta-hydroxyethyi) amine hydrochloride and 0.2% ammonium chloride. The treating solution has a pH of 2.3 and is used at room temperature. The yarn is centrifuged, dried at room temperature and heated in a current of air at C. for four minutes. The treated yarn is rinsed with water, heated at 70 C. for three minutes in a 0.1% soap solution, rinsed with water. and dried. As a result of this treatment, the yarn gains 4.5% in weight and has a wet tenacity 28% greater than the untreated control. When dyed with the acid dye, l-amino- 4 para-toluido anthraquinone 2,2 disulionic acid, and washed with a warm soap solution, the modified yarn has a blue color similar in shade and depth to that obtained with wool dyed and washed in an identical manner. Untreated viscose rayon is not colored by this dye.

It is to be noted that these advantageous results are not obtained when the salt of a primary or secondary hydroxyalkylamine is used. For example, a different result is obtained when the methyl-bis(beta-hydroxyethyl) amine hydrochloride in the above treatment is replaced with an equal quantity of beta-hydroxyethylamine hydrochloride and the viscose yarn is treated in a manner similar to that described above. The dye is not retained by the modified yarn when it is dyed with the acid dye, 1-amino-4-para-toluido anthraquinone-2,2'-disulfonic acid, and washed in the same manner a the methy1-bis(betahydroxyethyl) amine hydrochloride formalde- In addition, the treatment Fiber lowers the wet strength of the yarn considerably. Similar negative results are obtained when the beta-hydroxyethylamine hydrochloride is replaced with bis(beta-hydroxyethyl) amine hydrochloride.

Exmu III Skeins of 400 denier, 33 filament cellulose acetate yarn containing 45% combined acetic acid are impregnated at room temperature with an aqueous ethanol solution containing 40% ethanol, formaldehyde, tris (beta hydroxyethyl) amine hydrochloride and 0.2% ammonium chloride. The yarn is centrifuged, dried at room temperature, and heated in a forced draft oven at 125 C. for four minutes. The treated cellulose acetate yarn is rinsed with water, placed in a 0.1% soap solution at 70 C. for three minutes, rinsed with water and dried. The modified cellulose acetate yarn has good amnity for the acid wool dyes, l-amino 4 para-toluido-anthraquinone-2,2-disulfonic acid and Du Pont Milling Red SWB, Rowe Color Index No. 430. The dyeings on the modified acetate yarn possess about the same degree of fastness to soaping as similar Exam-rt: IV

Skeins of 2500 denier, 100 filament "Fiber D" yarn are impregnated with an aqueous solution containing 10% tris-(beta-hydroxyethyl) amine hydrochloride,'5% formaldehyde, and 0.3% ammonium chloride. The impregnated yarn is centrifuged so that the weight of treating solution retained is about equal to the weight of the dry yarn. The yarn is dried at room temperature in a stream of air and baked in a forced draft oven at 140 C. for three minutes. The treated yarn is rinsed with water, heated in a 0.1% soap solution at 70 C., rinsed again with water, and dried at room temperature. The treatment increases the wet strength of the yarn 100%. The modified "Fiber D" has good affinity for the acid wool dye, 1-amino-4-para-toluido-anthraquinone-2,2- disulfonic acid, and the direct cotton dye. Pontamine Sky Blue 63X, Rowe Color Index No. 518, and the dyeings are fast to soaping. The crease angle of the yarn is increased by this treatment from 66, that of the untreated "Fiber D," to 158. This indicates that the resilience of the treated yarn is markedly superior to the control.

The crease angle is determined by winding a single thread which has been conditioned at 50% relative humidity and 25 C. over a doubiaedged knife blade under a tension of 500 g., removing the tension after 10 minutes and cutting the thread along one edge or the knif blade. The creased segments of the yarn are allowed to relax for ten minutes while lying on a smooth horizontal surface. The degree that the thread recovers from creasing is an index of its resilience, and the angle formed by the thread is known as the crease angle. An increase in crease angle accordingly indicates improved resilience.

Exsmnn V Slreins of 2500 denier, 100 filament "Fiber D" yarn impregnated with an aqueous solution containing 5.0% tris- (beta-hydroxyethyl) amine hydrochloride, 3% formaldehyde, and 0.4% ammonium chloride is centrifuged so that amount of treating solution retained is equal to the original weight of the dry yarn. The skeins are dried at room temperature and then placed in xylene at 138' C. for one minute. The xylene is removed from the "Fiber D" either by evaporathe tlon or by rinsing with methanol. The yarn is then washed in a warm soap-soda ash solution, rinsed and dried. The yarn has gained 1.9% in weight and is improved 16% in wet strength. After being wet with water and centrifuged, the modified Fiber D" retains only 33% as much water as the untreated yarn. The crease angle of the treated yarn is as compared with 66 for the untreated "Fiber D." This indicates a considerable improvement in the resilience of the yarn.

Exams: VI

Bright, unfinished, 150 denier, 40 filament viscose rayon yarn is impregnated with an aqueous treating solution containing 4% formaldehyde, 15% phenyl-bis-.(beta-hydroxyethyllamine hydrochloride and 0.2% ammonium chloride. The treating solution, which has a pH of 1.8, is used at room temperature. The yarn is centrifuged, dried at room temperature and heated in a forced draft oven at C. for four minutes. The treated yarn is placed in a 0.1% soap solution at 70 C. for three minutes, rinsed with water and dried. The modified viscose rayon has good affinity for the acid wool dye, l-amino-i-para-toluido-anthraquinone-2,2'-disulfonic acid, and the dyeing is fast to soaping.

Exams: VII

Skeins of 700 denier-70 filament "Fiber D" yarn are impregnated with an aqueous solution containing 10% tris-(beta-hydroxyethyl)amine hydrochloride, 5% formaldehyde and 0.4% ammonium chloride. The yarn is centrifuged, dried at room temperature, and heated in a forced draft oven at 122 C. for two minutes. The treated yarn gains 2.4% in weight, is improved in wet strength and has afiinity for th acid dye, 1- amino-4-para-toluido-anthraquinone-2,2- disuL fonic acid, and the direct dye, Pontamine" Sky Blue BBX, Rowe Color Index No. 518.

It is to be understood, of course, that the above examples merely illustrate preferred embodiments and are not to be construed as defining the broad limits of the invention. On the contrary, a wide departure from the exact materials, reagents and conditions recited in the examples is obviously within the purview of this invention.

Thus, cellulosic textile materials suitable for use in this invention include natural cellulose products, such as cotton, Jute, ramie, and linen; regenerated cellulose materials, such as viscose and cuprarnmonium rayon; and cellulose esters and ethers containing unsubstituted hydroxyl groups, such as cellulose acetate. cellulose nitrate, cellulose acetate propionate, methyl cellulose, ethyl cellulose, benzyl cellulose, glycol cellulose, and cellulose glycolic acid. The textil material may be treated in the form of a fabric, loose staple, continuous filament yarn, and yarn spun from staple fiber. The celiulosic material may be mixed with other textile products, such as wool, either before or after treatment. The cellulose derivatives, such as th esters or others, which have fewer unsubstituted hydroxyl groups than cellulose, require the use of a greater excess of formaldehyde than other cellulose textiles in order to obtain the desired degree of modification.

The concentration of formaldehyde used will depend somewhat on the other reaction variables and the nature of the product desired. For example, less formaldehyde is required when longer baking times, higher baking temperatures, more active catalysts, or higher concentrations of the tertiary hydroxyalkylamine salt are used. More formaldehyde will be required when a crush re- The treating solution may be applied to the sistant product is desired. In general. at least textile material in any of several ways. The 1% formaldehyde is used and 5 to or even material may be dipped in the solution and as much as 40%. may be employed. The term squeezed or centrifuged to remove excess soluiormaldehyde" is meant to include monomeric 5 tion. Yarn, rope and fiat goods may be passed formaldehyde and such polymers as trioxane and continuously through the solution or the solution paraiormaldehyde. may be applied by spraying and the excess solu- Salts suitable for use in this invention include tion may be removed by squeezing between rolls those derived from strong acids and water-soluble or by vacuum extraction. The treating solution tertiary hydroxyalkylamines. all hydroxyl groups 1 is usually employed at room temperature although of which are at least 2 carbon atoms removed solutions at a higher or lower temperature may from the amino nitrogen. Suitable strong acids be used. include such mineral acids as hydrochloric, sul- The impregnated eellulosic textile material i'uric, phosphoric, hydrobromic, and organic acids may be dried in air at temperatures ranging from such as oxalic. chloroacetic and toluenesulionic. is room temperature to 70 C. or more. Uniform The tertiary hydroxyalkylamines may have one, and rapid drying is favored by the rapid circulatwo, three or more hydroxyl groups and should tion of air in the drying chamber. be soluble in water to the extent of at least 2% The impregnated and dried textile material is at 25 C. Salts of these water-soluble tertiary heated at temperatures ranging from 70 to 200 hydroxyalkylamines are suiliclently reactive so C. or higher in order to bring about reaction bethat products having the desired afllnlty for acid tween the textile material, formaldehyde and and chrome dyes are obtainable. Salts of tertiary tertiary hydroxyalkylamine salt within a reasonhydroxyalkylamines having a plurality of hyable time. At lower baking temperatures it is droxyl groups and a neutral equivalent less than necessary to heat as long as an hour or more 200 are preferred because they react more readily while at the higher temperatures a heating time with the cellulosic materials. and for a given of a minute or less is often sufllcient. The use increase in weight there is introduced into the f h gh r bakin temperatures favors the forms. cellulosic textile materials a greater amount of $10!! f cru h r ant Pr A vi r us cirtertiary amino nitrogen, which is essential for culation of air in the baking chamber improves acid and chrome dye amnity. the uniformity of the treatment and reduces the In addition t t salts of the tertiary hydroxytime required for the reaction to take place. An aikylamines used in the examples. salts of the inert "quid y be heatmfl mecu!!!- ioliowing water-soluble aike are n. Suitable inert liquids include xylene, dioxane, and able for use in mm invention; etmbbmmembis(methoxyethoxyethyl)ether. Other suitable hydroxyethyllamine, N beta-hydroxyethyl as heating media are described in Pinkney, U. S. phoune N N'-bls(beta-hydroxyethyl) piperazlne application Serial N0. November 8, tris(beta hydroxypropyllamine, N,N,N',N' tet- 1940: now Patent 21311-080- rakis(beta hydroxyethyl) ethylenediamine. di- 1 claim:

methyl-3-hydroxypropylamlne, dimethyl-(2,3- The method of treating ceilulosic textile hydroxypmpynamme and dimethybmmydmxw 40 materials to render them receptive to acid and buty1)amme chrome dyes while retaining their ailinity for did ab to 1 t 1 st 1 of t rect dyes which comprises impregnating the celg g f fig g ffifigg a :f luiosic textile material with an aqueous solution Hating bath in order to bt fibers having F Of a PH value within the range 0! 1.6 to 3.0 and preclable afllnity for acid and chrome dyes, and which contains from 3 to 15% by weight of form concentrations of 5 to 20%, or even as high as amehydefrom to 2% of an acidic catalyst or more, give good results with a given and from 3 to 30% of a water-soluble salt of a concentration of the tertiary hydroxyalkylamine wuebsomble ternary hydmxyalkylamme! each salt. higher concentrations of formaldehyde, achydroxyl group of wmch 15 at least 2 carbon five catalysts higher baking temperatures and 50 atoms removed from the amino nitrogen, substanlonger baking times all lead to products having drying the impregnated mateflaland there a higher degree of modification.

Acids and substances capable of liberating or becoming acids under the conditions of the treatment constitute suitable catalysts. Examples are mineral acids such as hydrochloric, sulfuric, phosphoric, and hydrobromic; acid salts of mineral acids such as sodium hydrogen sulfate, sodium dihydrogen phosphate; salts of strong acids and weak bases, such as ammonium chloride, ammonium sulfate, ammonium thiocyanate. 3 23332 23: 3; 2 by weight or form and ferric chloride: and organic acids such as tartaric, citric and toluenesulfonic. The concen- ';:gg? g 53,2 3; gmggfifi Particular catalyst may vary from amine, each hydroxyl group of which is at least 2 lower as high as 1% or depend carbon atoms removed from the amino nitrogen. ing upon its potential acidity. Preferably, su substantially drying the impregnated material in cient catalyst is used so that the pH of the imair at temperatures ranging from room temperapresnatlns o t on i e w e and Less ture to c.. and thereafter heating the same catalyst will be required when mo drastic 70 at a temperature of from about 70 C. to about ing conditions or higher concentrations of form- 200 c, t complete the re tion,

aldehyde are employed. The amount and type 3. The method of treating cellulosic textile of catalyst is selected so that the desired modimaterials to render them receptive to acid and ilcation oi the textile material takes place readily chrome dyes while retaining their affinity for diwith little or no tendering. 7: ram; dyes which comprises impregnating the cel- 5s 2. The method of treating cellulosic textile materials to render them receptive to acid and chrome dyes while retaining their afllnity for direct dyes which comprises impregnating the cellulosic textile material with an aqueous solution asenosa lulosic textile material with an aqueoussolution of a pH value within the range or 1.6 to 3.0 and which contains from 3 to 15% by weight of formaldehyde, Irom 0.05 to 2% of an acidic catalyst, and from 3 to 30% oi a water-soluble salt of a water-soluble tertiary hydroxyalkylamine having a plurality of hydroxyl groups and a neutral equivalent of less than 200, each hydroxyl group of which is at least 2 carbon atoms removed from the amino nitrogen, substantially drying the impregnated material, and thereafter heating the same at a temperature from about 70 C. to about 200 C. to complete the reaction.

4. The method of treating cellulosic textile materials to render them receptive to acid and chrome dyes while retaining their aiflnity i'or direct dyes which comprises impregnating the cellulosic textile material with an aqueous solution of a pH value within the range of 1.6 to 3.0 and which contains from 3 to 15% by weight of formaldehyde, from 0.05 to 2% or an acidic catalyst, and from 3 to 30% of a water-soluble salt oi. a water-soluble tertiary beta-hydroxyethylamine, substantially drying the impregnated material, and thereafter heating the same at a temperature of from about 70 C. to about 200 ,0. to complete the reaction.

5. The method of treating cellulosic textile materials to render them receptive to acid and chrome dyes while retaining their amnity for direct dyes which comprises impregnating the cellulosic textile material with an aqueous solution 01 a pH value within the range of 1.6 to 3.0 and which contains from 3 to 15% by weight of formaldehyde, from 0.05 to 2% of ammonium chloride as catalyst, and from 3 to 30% of a water-soluble salt of a water-soluble tertiary beta-hydroxyethylamine, substantially drying the impregnated material in air at temperatures ranging irom room temperature to 70 0., and thereafter heatcsnrrrrcym or consumer.

new no. 2,391,912..

It is hereby certified that erro of the above numbered patent requir ond column, line 51, ,tom 68'' read out ihonld be read with this correction therein which contains mm a to by weight oi. formaldehyde, from 0.05 to 2% of ammonium chloride as catalyst, from 3 to 30% 0! a water-soluble salt of a water-soluble tertiary beta-hydroxyallnvlamine, substantially drying the impregnated material in air at room temperature, and thereafter heating the same at a temperature within the range of to C. to complete the reaction.

7. The process of claim 1 wherein the cellulosic textile material is regenerated cellulose textile material.

8. The process of claim 2 wherein the cellulosic textile material is regenerated cellulose textile material.

9. The process of claim 5 wherein the cellulosic textile material is regenerated cellulose textile material.

10. The process of claim 6 wherein thecellulose textile material is regenerated cellulose tex'tile material.

11. The method of treating cellulosic textile materials to render them receptive to acid and chrome dyes while retaining their amnity for direct dyes which comprises intimately contacting the cellulosic material with an aqueous solution of a pH value within the range 0! 1.6 to 3.0 comprising essentially from 3 to 15% by weight of formaldehyde, from 0.05 to 2% of an acidic catalyst, and from 3 to 30% of trisibeta-hydroxyethyl) amine hydrochloride, substantially drying said cellulosic textile material, and thereafter heat treating the same to complete the reaction.

12. The method of treating regenerated cellulose textile materials to render them receptive to acid and chrome dyes while retaining their afllnity for direct dyes which comprises impregnating the textile material with an aqueous solution of a pH value within the range oi 1.6 to 3.0 and which contains from 3 to 15% by weight of formaldehyde, from 0.05 to 2% of ammonium chloride as catalyst, and from 3 to 30% of tris(beta-hydroxyethyDamine hydrochloride, substantially drying the impregnated material in air at room temperature, and thereafter heating the same at a temperature within the range oi 90 to 140' C. to complete the reaction.

WILLIAM J. BURKE.

January 1, 1914.6.

' WILLIAM J. BURKE.

r appears in the printed specification ing correction as follows: Page 2, sec- --6Bll--; and that the said Letters Putthat the some me'y conform to the record. or the case in the Patent Office.

si ned and use his 91mm; oi. April, A. 1:. 191m.

(Seal) Leslie Frazer l 'iret Assistant Gunieeioner o1 Patents.

asenosa lulosic textile material with an aqueoussolution of a pH value within the range or 1.6 to 3.0 and which contains from 3 to 15% by weight of formaldehyde, Irom 0.05 to 2% of an acidic catalyst, and from 3 to 30% oi a water-soluble salt of a water-soluble tertiary hydroxyalkylamine having a plurality of hydroxyl groups and a neutral equivalent of less than 200, each hydroxyl group of which is at least 2 carbon atoms removed from the amino nitrogen, substantially drying the impregnated material, and thereafter heating the same at a temperature from about 70 C. to about 200 C. to complete the reaction.

4. The method of treating cellulosic textile materials to render them receptive to acid and chrome dyes while retaining their aiflnity i'or direct dyes which comprises impregnating the cellulosic textile material with an aqueous solution of a pH value within the range of 1.6 to 3.0 and which contains from 3 to 15% by weight of formaldehyde, from 0.05 to 2% or an acidic catalyst, and from 3 to 30% of a water-soluble salt oi. a water-soluble tertiary beta-hydroxyethylamine, substantially drying the impregnated material, and thereafter heating the same at a temperature of from about 70 C. to about 200 ,0. to complete the reaction.

5. The method of treating cellulosic textile materials to render them receptive to acid and chrome dyes while retaining their amnity for direct dyes which comprises impregnating the cellulosic textile material with an aqueous solution 01 a pH value within the range of 1.6 to 3.0 and which contains from 3 to 15% by weight of formaldehyde, from 0.05 to 2% of ammonium chloride as catalyst, and from 3 to 30% of a water-soluble salt of a water-soluble tertiary beta-hydroxyethylamine, substantially drying the impregnated material in air at temperatures ranging irom room temperature to 70 0., and thereafter heatcsnrrrrcym or consumer.

new no. 2,391,912..

It is hereby certified that erro of the above numbered patent requir ond column, line 51, ,tom 68'' read out ihonld be read with this correction therein which contains mm a to by weight oi. formaldehyde, from 0.05 to 2% of ammonium chloride as catalyst, from 3 to 30% 0! a water-soluble salt of a water-soluble tertiary beta-hydroxyallnvlamine, substantially drying the impregnated material in air at room temperature, and thereafter heating the same at a temperature within the range of to C. to complete the reaction.

7. The process of claim 1 wherein the cellulosic textile material is regenerated cellulose textile material.

8. The process of claim 2 wherein the cellulosic textile material is regenerated cellulose textile material.

9. The process of claim 5 wherein the cellulosic textile material is regenerated cellulose textile material.

10. The process of claim 6 wherein thecellulose textile material is regenerated cellulose tex'tile material.

11. The method of treating cellulosic textile materials to render them receptive to acid and chrome dyes while retaining their amnity for direct dyes which comprises intimately contacting the cellulosic material with an aqueous solution of a pH value within the range 0! 1.6 to 3.0 comprising essentially from 3 to 15% by weight of formaldehyde, from 0.05 to 2% of an acidic catalyst, and from 3 to 30% of trisibeta-hydroxyethyl) amine hydrochloride, substantially drying said cellulosic textile material, and thereafter heat treating the same to complete the reaction.

12. The method of treating regenerated cellulose textile materials to render them receptive to acid and chrome dyes while retaining their afllnity for direct dyes which comprises impregnating the textile material with an aqueous solution of a pH value within the range oi 1.6 to 3.0 and which contains from 3 to 15% by weight of formaldehyde, from 0.05 to 2% of ammonium chloride as catalyst, and from 3 to 30% of tris(beta-hydroxyethyDamine hydrochloride, substantially drying the impregnated material in air at room temperature, and thereafter heating the same at a temperature within the range oi 90 to 140' C. to complete the reaction.

WILLIAM J. BURKE.

January 1, 1914.6.

' WILLIAM J. BURKE.

r appears in the printed specification ing correction as follows: Page 2, sec- --6Bll--; and that the said Letters Putthat the some me'y conform to the record. or the case in the Patent Office.

si ned and use his 91mm; oi. April, A. 1:. 191m.

(Seal) Leslie Frazer l 'iret Assistant Gunieeioner o1 Patents. 

